Old 240 circuit

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  #1  
Old 02-24-15, 06:56 AM
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Old 240 circuit

I have an old, unused dedicated 240 that used to power a thru the wall AC. I'd like to change that to 120. What choices do I have? Or what's the simplest way to do that. Thanks
 
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  #2  
Old 02-24-15, 07:02 AM
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You will remove the white wire from the breaker and connect it to the neutral bar with the other whites. One white per hole.

You will also need to change the receptacle to the proper 120 volt rated one.

Only make changes with the power off.
 
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Old 02-24-15, 07:10 AM
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You may have to change the breaker to a single pole breaker to accommodate the load anticipated by the wire size and load. You may have a 30 amp breaker, and need only a 20 for OCPD.
 
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Old 02-24-15, 07:44 AM
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Haha. Cut power off. Good rule to go by. You only forget that once don't you?
 
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Old 02-24-15, 07:47 AM
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It's currently on a 20 amp breaker. Thanks for the advice gentlemen. Sounds good.
 
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Old 02-24-15, 07:57 AM
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Above assumes it has a ground wire.
 
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Old 02-24-15, 10:11 AM
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Yes right, I haven't even looked yet. It's newer work so I assume it does but if not I'll use whatever's left over for a ground. Has to be at least three wires there.
 
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Old 02-24-15, 03:07 PM
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What makes you think that there must be three wires on this circuit? Straight 240 volt circuits only require two wires for operation, same as straight 120 volt circuits.

Besides, with #12 or #10 conductors you may NOT change the colors of the wire insulation to make an equipment grounding conductor. The ONLY times a conductor smaller than #6 may be re-identified is when cable with a white wire is used in a switch loop or a straight 240 volt circuit. Then the white is re-identified as a "hot" conductor by using any color other than white, grey or green.
 
  #9  
Old 02-24-15, 05:57 PM
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Jeez, sorry furd, I was thinking three conductor but it probably is two conductor and probably has a ground since it's newer but so long as I have two conductors that's all I need to make a very happy 120 circuit. Finding a ground will be gravy.

And yes I understand about rebranding the white as hot but thanks for reminding me.
 
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Old 02-24-15, 07:02 PM
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so long as I have two conductors that's all I need to make a very happy 120 circuit. Finding a ground will be gravy.
Really? You know it must be at the supplying panel not just anywhere?
 
  #11  
Old 02-26-15, 07:30 AM
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Just wondering---Isnt the current breaker a 2-pole one. Would you switch that out or can just one pole be used? Also, if you currenty have a red and black coming from the 2 poles, how do you use the current wires with a 120v terminal?
 
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Old 02-26-15, 07:41 AM
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Bork2, welcome to the forums! See post #3 regarding breaker. Post #8 regarding wire color. But to answer your question, you can't with red and black.
 
  #13  
Old 02-26-15, 09:16 AM
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I took out the receptacle. One blk one wht one bare grd #12 wire. I'll switch the breaker for a single pole 20 amp. All's good.

Chandler, please explain why you can't with red and black wires. There doesn't seem to be enough explanation on this forum, just you can or you can't.
 
  #14  
Old 02-26-15, 09:23 AM
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Not sure what you mean ray2047? At the supplying panel? You mean the 240 being two hot wires? Or remarking the white to black? The ground? Anyhow, I got it. Thanks.
 
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Old 02-26-15, 09:26 AM
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No color can be repurposed for a neutral. You can make a white wire, black in a switch loop, but the reverse is not code (making a red into white). You're good with the wiring you have going at present.
 
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